#48 – Bob Pease, Jim Williams – Posthumous Pease Porridge

Though it’s been a sad week for the field of analog engineering, we want to honor Bob Pease and Jim Williams’ passing. They were wonderful educators, engineers and people and we felt honored to even talk about them on the show. Please share any comments you might have about either of these two great men in the comments section.

Comments

I look forward to listening #48 during my roadtrip home from Syracuse tomorrow… I did have the honor of briefly meeting both Jim Williams and Bob Pease on separate occasions, and spending a short time exchanging stories with them. Both were truly great engineers and individuals in every sense. I HIGHLY recommend their books! It’s hard to imagine every finding successors that can write with such understandable styles.

and also a rant- ever since i switched to this silly iPhone, listening to theAmpHour is not the same. Itunes is slow to syndicate, and downloads stream and cache vs actually download, which is troublesome if you go through several dead zones while driving!

I guess what is great about a software defined radio is its reconfigurability in the field. After RF down conversion, the base band signal is processed by any combination of digital logic and software. This eliminates the use of traditional analog circuitry. Pretty much, just by implementing different DSP algorithms, you can decode any modulation scheme, eliminating analog circuitry (peak detector for AM, FM discriminator, etc). This means that some SDRs can potentially decode other modulation methods that aren’t known yet. Provided that the DSP can run on the SDR platform, you can support other modulation methods in the future.

I agree with Dave, this isn’t such a novel idea in that this has been done for ages. However, with the increasing capabilities and decreasing costs of processing power, the capabilities of what can be accomplished for a desktop computer is now quite substantial.

That is the key to SDR, it is agnostic to the modulation scheme, coding, etc so you can build a GSM base station, reprogram it for 3G and then reprogram it for 4G. To do that in traditional hardware would require racks of equipment. In SDR you just reprogram it. It isn’t that new (Plessey had a software receiver in the early 1980’s) but the capabilities have expanded enormously making it available to hobbyists with a performance every bit as good as a well built analogue design.

It was actually Baltic sea where tycho brache was launched from. Military area. Also the sequencer did not start at first and the parachute did not work correctly on the fall of the retrievable part of the rocket. Luckily the testing was a huge success.

For me, the launch was really emotional moment. I was at work on that time. And I forced a client to wait after me to see the launch. 😀

For first fliers, the builders want to do it and loads of enthusiasts are happy to volunteer when they get the chance.

Pease: Pease’s book was one of the first electronics book I recall reading after finishing school. Then I started reading is column. I met him in person and he helped me with a microphone circuit on a high-end hands-free conferencing system. I can’t believe he’s gone.SDR: I think of SDR as sampling the IF. The first stage converts the band your interested in into an IF. The second stage converts a particular frequency in the band to baseband to extract the message signal. SDR samples the entire IF at once with a high-speed ADC. Then the software algorithms determine the bandwidth of the filter that extracts the message signal and determines the modulation decoding method.Low-End Attack: This is covered in my new favorite business book, The Innovator’s Solution. When a technology is good enough, a disruptor appears with a low-price product to make it available to people who previously couldn’t afford it. Taking away the lowest-end customer feels good to the established company. You would enjoy The Innovator’s Solution.The 1st caller: Randy was clearly from Virginia IMHO.

Do you recall the Java CPUs and Java Stations from Sun from a VERY long time ago? These were specifically designed to run Java apps and would have been lightning fast… the idea was ingenious, close to fantastic! However as with all these things, it got ditched as the idea didn’t pick up…

Anyway, the Android chip is a good -naturally- idea that will get my support as Android user 🙂